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        <title>Simplify a LineString geometry</title>
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        <h1 id="title">Simplify a LineString geometry</h1>
        <div id="tags">
            Douglas-Peucker, Douglas, Peucker, Peuker, tolerance
        </div>
        <p id="shortdesc">
            Shows the usage of the method &quot;simplify&quot; that implements 
			the Douglas-Peucker algorithm to remove &quot;insignificant&quot; 
			vertices from LineString geometries.
        </p>
        <div id="control-simplify">
            <label for="tolerance">Tolerance factor:</label>
            <input name="tolerance" id="tolerance" type="number" min="0" max="1" step="0.02" value="0.1">
            <input type="button" id="simplify" value="Simplify LineString">
            <input type="button" id="animation" value="Start animation">
        </div>
        <div id="map" class="smallmap">
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        <div id="map-simplify" class="smallmap">
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            <p>
                Instances of OpenLayers.Geometry.LineString have a method simplify,
                that can be used to simplify linestring geometries.
                Simplification sometimes is useful to enhance the perfomance of 
                vector rendering or to reduce complexity of geometries. This 
                might be especially handy when viewing geometries a small 
                scales.  
            </p>
            <p>
                OpenLayers.Geometry.LineString::simplify is a recursive 
				implementation of the famous Douglas-Peucker algorithm. It is 
				controlled by a tolerance factor that defines the threshold for 
				vertices to be considered &quot;insignificant&quot; for the 
                general structure of the geometry.                
            </p>
            <p>
                The LineString on the left map can be simplified according to 
                the tolerance value one enters in the form-field above the maps.
                Use a value between 0 and 1 for best results. If you navigate 
                the left map, the right map will show the same location to make 
                it easier to spot the differeces between the LineStrings.
            </p>
            <p>
                You can also use the button &quot;Start animation&quot; to get 
                results for increasing tolerance-factors from 0.02 to 1.0. The
                animation can be paused by clicking on the button &quot;Stop
                animation&quot;. 
            </p>
            <p>
                The LineString represents a part of the coastline of 
                <a href="http://www.openstreetmap.org/?lat=54.7309684753418&amp;lon=83.1809234619141&amp;zoom=11">this 
                place southeast of Novosibirsk in Russia</a> &mdash; found via 
                <a href="http://ryba4.com/python/ramer-douglas-peucker">an
                example implementation of the algorithm in python</a>.
            </p>
            <p>
                For a detailled explanation of the algorithm see 
                <a href="http://en.wikipedia.org/wiki/Douglas-Peucker_algorithm">the
                Wikipedia article</a> or the original publication: David Douglas 
                &amp; Thomas Peucker, "Algorithms for the reduction of the 
                number of points required to represent a digitized line or its 
                caricature", The Canadian Cartographer 10(2), 112-122 (1973) 
                (<a href="http://dx.doi.org/10.3138/FM57-6770-U75U-7727">DOI: 
                10.3138/FM57-6770-U75U-7727</a>).
            </p>
            <p>See <a href="simplify-linestring.js">simplify-linestring.js</a>
                for the source code of this example.</p>
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